The Temperature Sense. 



WILLIAM NEWTON LOGAN. 



Science is indebted to Messrs. Blix, Donaldson,, Eulenberg and 

 Goldschieder for valuable contributions concerning the temperature 

 sense; nevertheless many of the phenomena connected with it 

 remain unexplained, and the future undoubtedly has much to reveal 

 concerning it. 



Briefly stated, the facts which have been established by the above 

 scientists are: That there are certain points on the skin which are 

 sensible to cold and certain ones which are sensible to heat; that 

 there are others which are insensible to either heat or cold; and that the 

 destruction of the epidermal layer does not destroy the temperature 

 end-organs. A more complete account of the history of the temper- 

 ature sense may be found in volume X of Tlie Mind. 



The following experiments, while not throwing any direct light on 

 the subject, may be of value in the way of suggestion: 



The first experiments of the writer were made with a view of locat- 

 ing the temperature spots on different parts of the body. Nothing, 

 however, worthy of notice was discovered, except that I found little 

 to confirm the theory that there are different sets of nerves for differ- 

 ent degrees of temperature. End-organs that were sensible to heat 

 were sensible to all degrees of it. Nevertheless I found a great dif- 

 ference in degree of intensity of sensation. For instance, when an 

 end-organ which gave a very strong sensation was found, there would 

 be surrounding it several end-organs gradually shading offjn intensity 

 of sensation as the distance from the central organ is increased. 

 These centers I have called radial centers, and in the following 

 experiments have noted the number in each section gone over. 



My first thought in reference to this phenomenon was, that 

 there is a central nerve; that from this nerve several others radiate; 

 and that the intensity of sensation decreases as the distance from the 

 central organ increases. But I have found nothing in the science of 

 histology to either prove or disprove it. 



In experimenting with the ear, it was found that what at first 

 appeared to be an increased number of cold spots was only hyperses- 

 thesia resulting from frost-bite. I next experimented with scars, but 



(301) KAN. UNIV. QUAK., VOL. UI., NO. 3, JAN., 1895. 



